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Daddy Long-legs Spider

Redback Spiders: Scientific name: Latrodectus hasselti

Description: Redback Spiders are found throughout Australia. They are common in disturbed and urban areas. They belong to the Family Theridiidae, which is found worldwide. The notorious Black Widow Spider (Latrodectus sp) of the United States is a close relative of the Redback Spider, and only differs in appearance by the absence of a red dorsal stripe. Other species of Latrodectus occur in the Africa Pacific Islands, New Zealand, Europe and North and South America.

Biology: Webs consist of a tangled, funnel-like upper retreat area from which vertical, sticky catching threads run to ground attachments. The Redback Spider favours proximity to human habitation, with webs being built in dry, sheltered sites, such as among rocks, in logs, shrubs, junk-piles, sheds, or toilets. Redback Spiders are less common in winter months. Daddy-long-legs Spiders and White-tailed Spiders are known to catch and kill Redback Spiders. Insects are the usual prey of Redback Spiders, but they are capable of capturing quite large animals, such as male trapdoor spiders, king crickets and small lizards, if they become entangled in the web. Prey-stealing is also common, with large females taking stored food items from others’ webs.

Identification: Female Redback Spiders are black (occasionally brownish) with an obvious orange to red longitudinal stripe on the upper abdomen, with the red stripe sometimes being broken, and an "hourglass" shaped red/orange spot on the underside of the abdomen. Juveniles have additional white markings on the abdomen. Females have a body about the size of a large pea (1cm long) and slender legs. The males are only about 3-4 mm long and its red markings are often less distinct. The body is light brown with white markings on the upper side of the abdomen, and a pale hour-glass marking on the underside. Spiders commonly mistaken for Redbacks include their close relatives, the Cupboard Spider (Steatoda sp), the Grey House Spider (Achaearanea tepidariorum) and other members of the Family Theridiidae. Many of these spiders have a similar life history and habits to the Redback Spider.

Habits: Male Redback Spiders do not produce a web, but may be found on the fringe of a female’s web, especially during the summer mating season. The male has to make overtures to the female to discover whether she is ready to mate, which can prove fatal if she mistakes him for prey. It has been found that in order to occupy the female’s attention during mating, the male spider offers her his abdomen by standing on his head and ‘somersaulting’ his abdomen towards her mouthparts. The female begins to squirt digestive juices onto the male’s abdomen while the first palp is inserted. If he is not too weak, he will manage to withdraw, and then insert the second palp. She will continue to ‘digest’ his abdomen. Most males do not survive this process, which seems to be unique to Latrodectus hasselti. Once the female has mated, she can store sperm and use it over a period of up to two years to lay several batches of eggs. She spends much time producing up to ten round egg sacs (1cm diameter), which are white, weathering to brown over time. Each egg sac contains approximately 250 eggs and only one to three weeks need to pass before more eggs can be laid. These sacs are suspended within the web. Sometimes small ichneumonid wasps parasitise them, puncturing each sac with tiny holes. When the tiny pale-green spiderlings hatch, they disperse by ballooning to another suitable nest site. Females mature on average in about four months. The smaller male matures on average in about 90 days. Females may live for two to three years, whereas males only live for about six or seven months.

Toxicity: Redback bites occur frequently, particularly over the summer months. More than 250 cases receive antivenom each year, with several milder envenomations probably going unreported. Only the female bite is dangerous. They can cause serious illness and have caused deaths. However, since Redback Spiders rarely leave their webs, humans are not likely to be bitten unless a body part such as a hand is put directly into the web, and because of their small jaws many bites are ineffective. The venom acts directly on the nerves, resulting in release and subsequent depletion of neurotransmitters. Common early symptoms are pain (which can become severe), sweating (always including local sweating at bite site), muscular weakness, nausea and vomiting. Antivenom is available. No deaths have occurred since its introduction.

First Aid: Apply an ice pack to the bitten area to relieve pain. Do not apply a pressure bandage (venom movement is slow and pressure worsens pain). Collect the spider for positive identification. Seek medical attention.

Huntsman Spiders: Scientific name: BaLaIsopeda, Isopedella

Australian Huntsman spiders belong to the Family Sparassidae (formerly Heteropodidae) and are famed as being the hairy so-called ‘tarantulas’ on house walls that terrify people by scuttling out from behind curtains. In fact, they are a diverse and relatively harmless group of spiders, with 13 genera and 94 described species.

Habitat & Distribution: Huntsman Spiders are found living under loose bark on trees, in crevices on rock walls and in logs, under rocks and slabs of bark on the ground, and on foliage. Dozens of the social huntsman species, Delena cancerides, can be seen sitting together under bark on dead trees and stumps (notably wattles) but they can also be found on the ground under rocks and bark slabs. Badge Huntsman Spiders are often found on foliage but some woodland species are burrow builders, with and without trapdoors. Huntsman spiders of many species sometimes enter houses. They are also notorious for entering cars, and being found hiding behind sun visors or running across the dashboard.

These genera are generally widely distributed throughout Australia, although Heteropoda is absent from most of South Eastern Australia and Tasmania has only a few Huntsman species, notably Delena cancerides and Neosparassus spp.

Identification: Huntsman spiders are large, long-legged spiders, measuring up to 15 cm across the legs. They are mostly grey to brown, sometimes with banded legs. Many huntsman spiders, especially Delena (the flattest), and including Isopeda, Isopedella and Holconia, have rather flattened bodies adapted for living in narrow spaces under loose bark or rock crevices. This is aided by their legs which, instead of bending vertically in relation to the body, have the joints twisted so that they spread out forwards and laterally in crab-like fashion ("giant crab spiders"). Both Brown (Heteropoda) and Badge (Neosparassus) Huntsman spiders have less flattened bodies.

Badge Huntsman Spiders (Neosparassus species, formerly Olios spp.) are usually fawn or grey on top, with distinctive colour combinations of black, white, orange or yellow under the abdomen (the ‘badge’) and colour bands on the underside of the front legs. Body lengths: 2 cm (female), 1.6 cm (male).

Brown Huntsman Spider (Heteropoda species) spiders are patterned in motley brown, white and black.

Habits, Mating & Reproduction: Food consists of insects and other invertebrates. In the genus Isopoda, the male and female Huntsman spiders have a lengthy courtship, which involves mutual caresses, with the male drumming his palps on the trunk of a tree. He then inserts his palps into the female to fertilise her eggs. The male is rarely attacked, unlike some other species, and in fact many huntsman spiders live peacefully together in large colonies. A silken retreat is often built for egg laying, as well as for moulting. Some species of Neosparassus build a silken retreat in foliage, often at ground level, by binding several leaves together with silk, while others construct shallow burrows or move into abandoned cicada burrows. The female Huntsman (Isopeda, for example) produces a flat, oval egg sac of white papery silk, and lays up to 200 eggs. She then places it under bark or a rock, and stands guard over it, without eating, for about three weeks. During this period the female can be quite aggressive and will rear up in a defensive display if provoked. Some species will even carry their egg sac under their bodies while moving about. Delena females lay a ground-sheet of silk upon which the egg sac is anchored while the eggs are laid into it. They will then complete her egg sac and pick it up, leaving the silk ground-sheet behind. Incubation periods vary and are probably influenced by climatic conditions. In some cases (Isopeda), the female may moisten and tear the egg sac open, helping her spiderlings to emerge. The mother stays with them for several weeks. Young Huntsman spiders are pale, with the young of Neosparassus often being green in colour. They undergo several moults while still with their mother, hardening to a darker brown, and eventually disperse.

Huntsman spiders, like all spiders, moult in order to grow and often their old skin may be mistaken for the original spider when seen suspended on bark or in the house. The lifespan of most Huntsman species is about two years or more.

Predators of Huntsman Spiders include birds and geckoes, Spider Wasps, nematode worms and egg parasites (wasps and flies).

Bites: Huntsman spider bites usually result only in transient local pain and swelling. However, some Badge Huntsman spider bites have caused prolonged pain, inflammation, headache, vomiting and irregular pulse rate.

First Aid: Cold pack may relieve local pain. Seek medical attention if symptoms persist.

White-tailed Spiders: Scientific name: BaLampona cylindrata

Features: White-tailed Spiders have a dark reddish to grey, cigar-shaped body (males about 12 mm, females up to 18 mm long) and dark orange-brown banded legs. The grey dorsal abdomen bears two pairs of faint white spots (less distinct in adults) with a white spot at the tip; the male has a hard, narrow plate or scute on the front of the abdomen. The two common species in southern Australia, Lampona cylindrata and L. murina, are similar in appearance and have overlapping distributions in the south-east. Their bites have been controversially implicated in causing severe skin ulceration in humans.

Distribution: Lampona cylindrata is found across southern Australia (south east Queensland, New South Wales, Victoria, South Australia, Tasmania, Western Australia). Lampona murina is present in eastern Australia from north-east Queensland to Victoria (Queensland, New South Wales, Victoria).

Biology: White-tailed Spiders are vagrant hunters that live beneath bark and rocks, in leaf litter, logs and detritus in bush, gardens and houses. Tufts of specialised scopulate hairs on the ends of their legs allow them to walk easily on smooth or sloping surfaces. They make temporary silk retreats and spin disc-shaped egg sacs, each containing up to 90 eggs. They are most active at night when they wander about hunting for other spiders, their preferred food. They have been recorded eating curtain-web spiders (Dipluridae), daddy-long-legs spiders (Pholcidae), Redback Spiders (Theridiidae) and black house spiders (Desidae). During summer and autumn White-tailed Spiders are often seen in and around houses where they find both sheltered nooks and crannies and plenty of their favoured black house spider prey.

Human Intetraction/Threats: White-tailed Spider bites can cause initial burning pain followed by swelling and itchiness at the bitten area. Occasionally, weals, blistering or local ulceration have been reported – conditions known medically as necrotising arachnidism. As well as the spider’s venom, minor bacterial infection of the wound may be a contributory factor in such cases. A debate continues about the involvement of White-tailed Spider bite in cases of severe ulcerative skin lesions seen in patients diagnosed as probable spider bite victims. Typically, in such cases no direct evidence of spider bite is available. Sensational media reporting of supposed cases of severe "necrotising arachnidism" has given the White-tailed Spider a bad reputation. However, a recent study has monitored the medical outcomes of over 100 verified White-tailed Spider bites and found not a single case of ulceration (confirming the results of an earlier study). The available evidence suggests that skin ulceration is not a common outcome of White-tailed Spider bite. White-tailed Spiders around your house can be controlled by catching and removing any that you see and by clearing away the webs of the house spiders upon which they feed.

House Spiders: Scientific name: Badumna insignis

Description: Black and Grey House Spiders are common in urban areas, and are sometimes called Window Spiders. Other Ba dumna group spiders are found throughout Australia. They belong to the Family Desidae. Black and Grey House Spiders are widely distributed in southern and eastern Australia. Their webs form untidy, lacy silk sheets with funnel-like entrances. Black House Spiders are found on tree trunks, logs, rock walls and buildings (in window frames, wall crevices, etc). Badumna longinquus may be found in similar locations and often builds webs on foliage.

Identification: The Black House Spider (Badumna insignis) is a dark robust spider, with the female (up to 18mm) being larger than the male (about 9mm). The carapace and legs are dark brown to black, and the abdomen is charcoal grey with a dorsal pattern of white markings (sometimes indistinct). B. longinquus (Grey House Spider) is a slightly smaller (14mm) species with a greyish carapace and grey-brown banded legs. The webs of Black House Spiders have a ‘funnel-like’ shape, which is sometimes misunderstood as a Funnel-web Spider web. However, the two spiders are not at all similar in appearance, size or life history. See the Funnel-web Spider factsheet to compare the two spiders. The retreat of a true Funnel-web Spider is often less funnel-like and is usually a burrow in the ground. Some funnel webs have burrows in tree-trunk crevices but their web entrances are disguised with detritus (eg, bark) particles embedded in the silk, whereas the silk of Badumna webs is clean.

Habits: The female spider never leaves her web unless forced to, but keeps on repairing it – old webs can look grey and woolly from constant additions of silk. Males, when ready to mate, go in search of females in their webs. The male plucks the web of the female to attract her attention. Once the male has made sure that the female will be receptive, he can safely approach and inseminate her with his palps. They may then stay together for several days and may mate again several times. The female constructs several white silk egg sacs, which are secured within the web retreat. The female stays with the eggs until they hatch. The spiderlings then disperse. The spiders mature during summertime and live for about two years. In the bush, Badumna spiders are found especially upon rough-barked trees which provide good shelter for their retreats amongst the cracks in the bark. Trees that have been attacked by wood-boring insects are particularly attractive, as the sap flowing from the bored holes attracts flies, beetles, butterflies, bees and ants, which the spider can prey upon easily. In the house, they feed upon household pests attracted to the light of windows and lamps, where the spiders tend to build their webs. Enemies include the White-tailed Spider, as well as parasitic wasps and flies.

Bites: Black House Spiders are timid animals and bites from them are infrequent. The bite may be quite painful and cause local swelling. Symptoms such as nausea, vomiting, sweating and giddiness are occasionally recorded. In a few cases skin lesions (Necrotising Arachnidism) have developed after multiple bites.

First Aid: A cold pack may relieve local pain. Seek medical attention if symptoms persist.

Daddy Long Legs Spider: Scientific name: Pholcus phalangioides

Description: The Daddy Long-legs Spider belongs to a group of 12 Australian species known as the tangle-web spiders. It builds irregular webs in sheltered areas such as houses, garages and sheds. It feeds on insects and other spiders. It is one of the most common spiders in Australia as it has adapted to living in houses.

Toxicity: There is a belief that the Daddy Long-legs Spider has the most toxic venom of all spiders.However, there is no scientific evidence to back this up. It has tiny fangs cannot break human skin. Daddy Long-legs Spiders can actually kill and eat a Redback Spider so perhaps that is the origin of its venomous reputation.

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